This project continues the investigation of Ultrasonic forces coupled with Field-Flow Fractionation methods to separate macromolecules and cells. A prototype Ultrasonic Field-Flow Fractionation apparatus has been designed, fabricated and tested. The device is configurable in three modes. Retention has been demonstrated in the apparatus for particles ranging from l00nm to 80 micromoles, and effects due to various parameters such as acoustic amplitude, frequency, wave mode, flow rate and particle size were evaluated experimentally to confirm predicted behavior. Separations have been shown to be rapid and achieved at low intensities compared to other acoustic methods. Phase I will investigate feasibility of expanding the new technology for the separation of blood plasma proteins and hemoglobin. The project will advance modeling of acoustic and flow parameters, and develop an associated apparatus optimized for separation of macromolecule blood plasma components. A prototype USFFF device targeting l to 100nm particles will be designed, fabricated and tested in Phase I. PROPOSED COMMERCIAL APPLICATION: The technology should be well received in laboratories throughout the world to aid in analysis, synthesis, separation and study of complex, particulate systems in the chemical, biological and health sciences. The device adds compressibility as a separation variable along with density, particle size, and shape.